Bone mineral density (BMD), a critical measurement of overall bone health, relies on a dynamic remodeling process of concurrent deposition and resorption of bony matrix. BMD increases throughout childhood, reaching peak levels in early adulthood, then gradually decreases with age. Bone remodeling is sensitive to several nutritional, hormonal, immunological, lifestyle, and genetic factors, which can impact the rate of BMD loss with aging. Further, bone remodeling responds to repetitive mechanical loading by increasing bone mineral deposition, suggesting that differences in bone loading could modify associations between age and BMD by buffering weight-bearing regions against resorption. This study examines the association between age and BMD in 12 anatomical regions using survey, DXA, and laboratory data from adult NHANES participants (2007-2018 cohorts; n=12,260). In a linear regression adjusted for BMI, gender, race/ethnicity, and sedentary time – among other health and lifestyle variables – females have lower BMD than males in all regions regardless of age. Individuals who identified as non-Hispanic Black have significantly higher BMD in every region than the non-Hispanic White group. Proxies for socioeconomic status are positively associated with BMD in high-stress regions of the lower limb (i.e., total femur, femoral neck, trochanter, and the inter-trochanteric region) only. In the same regions, heavy smokers have lower BMD than non-smokers. Increased sedentary time is associated with lower BMD only in the arms (all p<0.01). Our presentation will further discuss how more rigorous statistical modeling may help identify and investigate the biological mechanisms underlying age-BMD associations and their impact on bone health and aging.